Mountain Bean Root (Shandougen)

Mountain Bean Root original: 山豆根 (Shandougen); the root of Sophora tonkinensis grows in the mountain valleys of Jiannan a historical circuit/region comprising parts of modern Sichuan and Chongqing. Today, it is also found in Guangxi. Those harvested from the prefectures of Zhong and Wan modern-day Zhong County and Wanzhou in Chongqing are of the highest quality.

The plant's seedlings and vines resemble those of common beans, which is why the root is named accordingly. Its leaves are green and do not wither even during the winter months. The roots are harvested for medicinal use in the eighth month of the lunar calendar.

Those varieties found in Guangnan a region covering parts of modern Guangdong and Guangxi resemble a small locust tree 槐 (Huai)|The Chinese Scholar Tree or Sophora japonica; here used as a botanical comparison for the leaf shape, reaching a height of just over one foot.

Its nature is cold and non-toxic. It is primarily used to neutralize toxins from various medicines and drugs. It is also effective at relieving pain and dissipating the toxic swellings of sores and abscesses. It is used to treat both humans and horses for Acute Yellowing (Jihuang)|a severe and rapid onset of jaundice, historically associated with infectious diseases or organ failure, as well as for fevers and coughing. It is also used to kill small parasites.